Indicating device



NOV. 28, 1933. A Q KlNYON INDICATI'NG DEVICE Filed Aprilvv 2, 1929 Patented Nov. 28, 193.3

UNITED STATES PATENT "o1-FICE Pa., Allentown,

by Allentown National Bank, executor,

Pa., assignor, by menne assignments, to Fuller Company, Catasanqua, Pa., a corporation of Delaware Application April 2, 1929, Serial No. 351,963, and in Germany June 30, 1923 5 Claims.

This invention relates to signal devices for conveying systems and hasparticular application to a system which is intended to be used for the conveying and distribution of material in a finely 5 divided state. It offers numerous peculiar advantages in connection with the handling of pulverulent material which is stored at a central point and then distributed to various remote points to be used; -for instance, the devices of this invention are particularly adapted for use in connection with systems for the handling of pulverized fuel. The details of the invention will therefore be described in that adaptation a1- though it is to be understood that the utility of the principles of the invention is not limited to any particular pulverulent material and the use of the term pulverized fuel is intended to include .other similar materials which may be handled by this system with equal facility.

pulverized fuel to carry on the grinding and pulverizing operations in some central location, from which the pulverizedmaterial is distributed either directly from the pulverizers, weigh bins or storage bins, to the bins from which the material is conveyed to the burners. Frequently the latter bins are located at'points which are spaced apart considerable distances and it is therefore desirable to provide a system of conveying the material to these bins for automatically controlling the distribution of material to the bins where it is required, and may also be advised by suitable indicating devices as to the condition of such bins at all times.

In Patent No. 1,857,643, which matured from copending application Serial No. 697,723, led March 8, 1924, of which the present application is in part a divisional application and in part a continuing application, is shown such a conveying system and it involves the use of a pump or other similar device which propels the material through a system of transport lines which are of a size appropriate to the quantity of material which is to be distributed. These lines extend to the several bins in which the material is to be deposited and each bin is connected with the main line. Located at each bin is a valve arranged so that the operator may shut off the now of material beyond this bin and cause the entire flow to pass into the bin. These valves are operated both automatically and by remote control by mechanism under the control of the operator and devices located at the operators station indicate the positions of the several valves.

The present invention relates to the provision It is customary in connection with the use of (Cl. ZOO-81) of devices at each bin which are brought into action when the material in the bin reaches certain predetermined levels and these devices cause remote indicators at the central station to give a signal or to operate their corresponding valves or both. Each bin may have a device to show the operator when it is full and another device which shows when the contents of the bin has reached a'certain low level. The high level indicator in the bin may be adapted to give a visual or audible warning signal to notify the operator to shut off the supply of pulverized material to that bin, or automatically to close the valve while, conversely, the low level indicator may be adapted to give a similar signal to notify the operator that the bin is empty, or nearly so, or automatically open the valve, so that the bin may be relled.

In its preferred form, the signal devices of this invention include a pendulum suspended within the bin and extending toward the bottom thereof in such a way that the rising material flowing more or less laterally toward the pendulum ln the bin as it is being filled, moves the pendulum from its normally vertical position, and as the material is withdrawn from the bin so that it no longer engages the pendulum, the latter returns to its normally vertical position. Suitable signal means such as electrical contact devices for operating remote indicators and control circuits are preferably actuated when the pendulum is in the vertical and in the inclined positions, thereby respectively indicating that the bin is lled, or nearly so, and that the bin is empty, or

nearly so. In order to give a more accurate indication for observing the condition of the bin at all times, whether material is being supplied to or withdrawn from the bin, several penduiums of different length may be employed in each bin. For example, a long pendulum extending nearly to the bottom of the bin controls the signal system in such a way as to give information that the bin is not full or nearing emptiness, while a short paddle near the top of the bin gives a signal when the bin is full.' Obviously, several intermediate 100 pendulums may be employed to indicate the exact level of the material in the bin at all times.

For a better understanding of the invention, reference is made to the accompanying drawing, in which 105 Figure 1 is an elevation of a pulverized fuel bin equipped with the signal system of this invention; Figs. 2 and 3 are enlarged vertical sectional views of the signal device which forms the principal element of the signal system; no

Figs. 4 and 5 are modified forms of the same; Fig. 6 is a diagram of a simplified electrical signal circuit adapted to be operated by the signal device, and l Fig. 7 is a modiiied form of mercury switch.

Referring to the drawing, and first to Fig. 1,

numeral 10 designates a bin for storing pulverized material, this material being supplied to the bin through pipe 11 by pumping, pneumatic or other 10 conveying means. The bin 10 may be of any desired form such as that shown in Fig. 1, and may be provided with a vent stack 12. On the top of the bin 10 is located one or more of the mechanisms 13 by which the signals at the central sta- 15 tion are energized to indicateV the condition of the bin as to the content thereof, or to close a valve operating circuit.

' Each device consists of a pendulum 14 which is suspended from the top of the bin 10 and which carries a paddle 15 at its lower end. This paddle is mounted in such a location that it is moved from its vertical position by the ow of material over the top of the pile in the bin as the latter is being filled. The pendulum 14 extends upwardly through a slot 16 in the top of the bin and a registering slot formed in the base 17. A

canvas sleeve 18 is secured to the pendulum 14- and to the base 17 around the slot 16 so that the entrance of dust from the bin into the casing o may be prevented. The pendulum is pivoted between hardened steel points 19 formed on the end of threaded members 20 which are secured in suitable lugs on frame 21, these threaded members 20 being capable of adjustment as may be'desired,

and being held in adjusted position by suitable jam nuts 22. v

The upper end of the pendulum 14 which is flattened in order that it may provide a suitable bearing surface for the points, is connected by 4a suitable links 23, 23', which are, in turn, con- I nected by a turn buckle 24 to one arm of a bell crank 25 pivotally mounted in a lug 26forming part of frame 21 and extending upwardly from the base 17 of the device- For use in connection with electric signals and valve operating mechanisms, the free arm of this bell crank 25 carries a mercury switch which consists of a sealed glass tube 27 having a quantity of mercury 28 within it. Sealed in the opposite ends of the tube are contact pairs 29 and 30 which are so arranged that when the tube is tilted to permit the mercury to lie either in one end or the other, a circuit will be closed between the adjacent contacts of eitherpair 29 or 30 and the mercury. One of the contacts 30 at one end of the tube may be connected with a suitable lamp 31 at the switchboard, and one of the contacts 29 at the other end of the tube is connected to solenoid 32 or other valve operating device, the other contactsof each pair being joined by a common lead supplied by a source of electric current 33 which controlled by hand switch 34.

It will be' apparent that movement of the pendulum 14 about points 19 toward the right as seen in Fig. 2 when the material in the bin piles up against the left-hand side of paddle 15, the

\ tube 27 will be tilted so that the mercury 28 flows to the other end thereof to close the circuit through contacts 29 and consequently solenoid 32,

while the circuit through contacts 30 and lamp 3Lhas been broken.

In order that the angle of tilt of the tube 27 may be adjusted to be actuated by various swings of the pendulum 14 so as to vary the sensitivity u thereof, links 23 and buckle 24 may be adjusted toward or away from pin centers 19 by placing the cotter pin 35 in any one of the holes provided in the attened portion of pendulum 14, as shown in Fig. 2. The electrical wires leading to the mercury switch 27 are preferably enclosed in a conduit 36 communicating with a groove 37 formed in base 17. 'Ihe entire operating mechanism is enclosed by a dust-proof hood or cover 38, which is preferably hinged at one side 39, while a bolt or nut 40 may be released from lug 41 so that the cover 38 may be raised about its hinge 39 for inspection or repair of the mechanism covered thereby.

Figs. 4 and 5 illustrate a modified form of the signal device which includes a cup-shaped base plate 42 secured to the top of bin 10 over a gasket 43, the wall of this plate being provided with electrical conduit opening 44 and bevelled at its edge for receiving the close-itting cover 45, which is secured to the base plate 42 by removable tap screws or bolts 46. The base plate 42 is also provided with a central opening 47 through which pendulum 14 is suspended from the hardened points of set screws 48 which are locked in position or extensions 49 by jam nuts 50. 'Ihe upper end of pendulum 14 is provided with a crossbar 51 through opposite ends of which tap screws 52 are threaded, these screws being adjustable in bar 51 and locked in place by jamb nuts 53. Placed directly above the tips of screws 52, so as to be engageable thereby, is a tilt plate 54 which is pivoted at its center upon the hardened points of set screws 55 which are threaded in extensions 49 and locked in place by jamb nuts 56. This tilt plate carries the mercury switch 27 secured in suitable brackets 57, the electrical wires from the contacts 29 and 30 passing through conduit 44.

Screws 52 are adjustable to tilt the switch tube 27, so that the circuit is closed through one of the sets of contacts 30 as shown, whereby light 31 is energized to indicate that the bin is nearing emptiness, while movement of the pendulum 14 to the right as seen in 4 will cause screws 52 to tilt the tube in the opposite direction to close the circuit through contacts 29 and light 32, indicating that the bin is nearly full. The angle of tilt of the mercury switch 27 may be varied merely by adjusting screws 52. In Fig. 5 the switch 27 is shown as placed at one side of tilt plate`54 so as to provide a place for a second switch when the indicator is used in special installations. A canvas sleeve 58 is secured to pendulum 14 and to base plate 42 so as to prevent.

the entrance of dust through 4opening 47.

The bin may contain a short pendulum as well as a long pendulum as shown in Fig. 1, the long 4pendulum indicating low bin, and the short pendulum indicating high bin. This long and short pendulum arrangement is of especial advantage inthe last bin where a number of bins in series are employed in the manner described in the aforesaid copending application. As these bins are filled in sequence, the movement of the short pendulum in the last bin indicates that all of the bins are full and that the material conveying means must be shut olf. The electrical ci`rcuit controlled by this short pendulum may give a special signal, such as an audible one, or it may shut off the conveying means. Any number of such pendulums of different lengths may obviously be used to indicate different material levels in -abin.

While the devices which have just been designals for indicating both the high and low levels of the material in the bin, it has been found that the device which indicates the low level is likely, under certainconditions, to give a wrong indication unless provision is made to permit the pendulum to swing in both directions away from a vertical axis. This is due to a tendency of the pulverized material to rathole directly over the point where it is being withdrawn at the bottom of the bin and as the material continues to feed out of the bin slides occur which ll up the rathole. Sometimes as a result of these slides the signal pendulum is carried back to its vertical position, although when thevsliding material has reached a condition of repose its level may be considerably above that of the paddle. This would cause the signal to give the wrong indication. This difficulty, however, has been overcome by slight modification in the construction of the device. For this purpose the base of the device is cut away slightly as at 59 in Fig. 2 so as to permit the pendulum arm to move to either side of its vertical position, and the mercury switch is given the modified form illustrated in Fig. 7. In this figure it will be noted that the glass tube 27 has a depresson 59 mid-way of its ends and the contact members 60 sealed through the tube are so located that when the tube is exactly in its horizontal position, the mercury will lie in the depression and will electrically connect both contacts.

However, if the tube is tilted slightly one way or the other the mercury will travel to the lower end of the tube and but a slight movement is l necessary in order to throw the mercury away -the paddle associated with this indicator.

tical.

from the contacts and thus break the circuit. These contacts are connected with a lamp at the central station so that when the tube is in horizontal position the lamp is lighted, thus indicating that the material is at or below the height of When the tube is moved to either side of its horizontal position, the lamp goes out and in the case of a slide the pendulum will ordinarily move from an inclined position at one side of the vertical, to an inclined position on the other side. In this case the lamp at the central station would simply make a ash, but would not continue lighted unless the pendulum came to rest exactly ver- The probabilities of this occurring upon a slide taking place are so slight that the signal has been vfound to work satisfactorily under normal operating conditions.

It will be seen that the new indicating device is extrem/ely simple and effective for electromechanically indicating the level of material in a container or bin, especially pulverent material which has been dinicult to handle heretofore because of the false repose of the material, whereby the usual' indicators are Ywholly ineiective. While a preferred mechanical and electrical arrangement of parts has been illustrated and decured to the lower end of said member and adaptedrto be engaged and moved by materials flowing generally laterally in the bin, switchv means tilted from a normal position, and means for transmitting to said support the movements of said pendulous member in either angular direction on its pivot and produced by materials in said bin flowing against said paddle.

2. An actuating device for indicators and the like adapted to be used on closed storage bins for ne material, which comprises the combination of a base for attachment to the top of the bin and having an opening to lie over an opening in the bin top, a pendulous member pivotally mounted on the base and extending downward through said opening in the base, a paddle secured to the lower end of said member and adapted to be engaged and moved by materials flowing generally laterally in the bin, switch means mounted on said base and including a pivotally mounted switch support and a switch mounted on said support having fully enclosed contact members and operable to make a circuit upon being tilted from a normal position, and means for transmitting to said support the movements of said pendulous member in either angular dlrection on its pivot and produced by materials in said bin owing against said paddle.

3. An actuating device for indicators and the like adapted to be used on closed storage bins for ne material, which comprises the combination of a base for attachment to the top of the bin and having an opening to lie over an opening in the bin top, a pendulous member pivotally mounted on the base and extending downward through said opening in the base, a paddle secured to the lower end of said member .and adapted to be engaged and moved by materials flowing generally laterally in the bin, switch means mounted on said base and including a pivotally mounted switch support and a switclL .of a base for attachment to the top of the bin and having an opening to lie over an opening .in the bin top, a pendulous member pivotally mounted on the basevand extending downward through said opening in the base, a paddle secured to the lower end of said member and adapted to be engaged and moved by materials flowing generally laterally in the bin, switch means mounted on said base and including a pivotally mounted switch support and a switch p on said support and operable to make a circuit upon being tilted from a normal position, means for transmitting to said support the movements of said pendulous member in either angular direction on its pivot produced by materials in said bin ilowing against said paddle, flexible means secured to the base and to the pendulous member beyond the base for preventing the passage of dust through the opening in the base, and a.M

cover on the base for enclosing the switch means and transmitting means. 5

5. An actuating device for indicators and the like and adapted to be used on ne material stcoraize-bins'.'v whichxcomprise's the combination either direction from anormal position. and

of a base for attachment to the top of the bin means for transmitting the movements of said 4armi having an opening to lie over an opening in pendulous member in either angular direction the bin top, a penduious member pivotaily reiativetoits pivottosaid support.

5 mounted on the base and extending downward 80 through said opening in the base, a paddle se- ALLENTOWN NATIONAL BANK, cured to the lower end of said member, switch Executor of the Estate of Alonzo G.

means mounted on said base and including a 'Kim/on, Deceased, -pivotaiiy mounted switch support and a switch By HAROLD W. PRETZ,

1o operable `to makera circuit upon being ltilted'in y `Trust Opcer. 85

so y 105 5o I l 125 55, l L w B5 l I v14o t 

